5.17 点灯实验（底层驱动）

1.led1点亮

mycdev.c

#include 
#include 
#include 
#include 
#include 
#include "head.h"
unsigned int major;
char kbuf[128]={0};
unsigned int *vir_moder;
unsigned int *vir_odr;
unsigned int *vir_rcc;

//分装驱动中的操作方法
int mycdev_open(struct inode *inode,struct file *file)
{
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
ssize_t mycdev_read(struct file *file,char *ubuf,size_t size,loff_t *lof)
{
    int ret;
    if(size > sizeof(kbuf))
    {
        size = sizeof(kbuf);
    }
    ret=copy_to_user(ubuf,kbuf,size);
    if(ret)
    {
        printk("copy_to_user faild\n");
        return ret;
    }
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
ssize_t mycdev_write(struct file *file,const char *ubuf,size_t size,loff_t *lof)
{
     int ret;
    if(size > sizeof(kbuf))
    {
        size = sizeof(kbuf);
    }
    ret=copy_from_user(kbuf,ubuf,size);
    if(ret)
    {
        printk("copy_from_user faild\n");
        return ret;
    }
    if(kbuf[0] == '1')//开灯
    {
        (*vir_odr) |= (1 << 10);
    }
    else if(kbuf[0] == '0')//关灯
    {
        (*vir_odr) &= (~(1 << 10));
    }
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
int mycdev_close(struct inode *inode,struct file *file)
{
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
//定义操作方法的结构体变量
struct file_operations fops={
    .open=mycdev_open,
    .read=mycdev_read,
    .write=mycdev_write,
    .release=mycdev_close,
};
static int __init mycdev_init(void)
{
    //字符设备驱动注册
    major=register_chrdev(0,"mycdev",&fops);
    if(major < 0)
    {
        printk("字符设备驱动失败\n");
        return major;
    }
    printk("字符设备驱动成功,maj,major=%d\n",major);
    //对led1相关的寄存器进行映射
    vir_moder = ioremap(PHY_LED1_MODER,4);
    if(vir_moder == NULL)
    {
        printk("寄存器映射失败%d\n",__LINE__);
        return -ENOMEM;
    }
    vir_odr = ioremap(PHY_LED1_ODR,4);
    if(vir_odr == NULL)
    {
        printk("寄存器映射失败%d\n",__LINE__);
        return -ENOMEM;
    }
    vir_rcc = ioremap(PHY_LED1_RCC,4);
    if(vir_rcc == NULL)
    {
        printk("寄存器映射失败%d\n",__LINE__);
        return -ENOMEM;
    }
    printk("寄存器映射成功\n");
    //寄存器初始化
    (*vir_moder) &= (~(3 << 20));//moder寄存器设置为输出模式01
    (*vir_moder) |= (1 << 20);
    (*vir_odr) &= (~(1 << 10));
    (*vir_rcc) |= (1 << 4);
    printk("寄存器初始化成功\n");
    return 0;
}
static void __exit mycdev_exit(void)
{
    //取消内存映射
    iounmap(vir_moder);
    iounmap(vir_odr);
    iounmap(vir_rcc);
    //字符设备驱动注销
    unregister_chrdev(major,"mycdev");

}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

demo.c

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "head.h"
int main(int argc, char const *argv[])
{
    char buf[128] = {0};
    int fd = open("/dev/mycdev", O_RDWR);
    if(fd < 0)
    {
        printf("设备文件打开失败\n");
        exit(-1);
    }
    while(1)
    {
        printf("请输入要进行的操作：1（开灯），0(关灯)>");
        fgets(buf,sizeof(buf),stdin);
        buf[strlen(buf)-1] = '\0';
        write(fd,buf,sizeof(buf));
    }
  
   
    close(fd);
    return 0;
}

head.h

#ifndef __HEAD_H__
#define __HEAD_H__

#define PHY_LED1_MODER 0x50006000
#define PHY_LED1_ODR 0x50006014
#define PHY_LED1_RCC 0x50000A28

#endif

2.写程序控制三盏灯的亮灭

head.h

#ifndef __HEAD_H__
#define __HEAD_H__

typedef struct
{
    unsigned int MODER;
    unsigned int OTYPER;
    unsigned int OSPEEDER;
    unsigned int PUPDR;
    unsigned int IDR;
    unsigned int ODR;
    unsigned int BSRR;
    unsigned int LCKR;
    unsigned int AFRL;
    unsigned int AFRH;
    unsigned int BRR;   
}gpio_t;
#define PHY_LED_RCC 0x50000A28
#define PHY_LED_MODER_E 0x50006000
#define PHY_LED_MODER_F 0x50007000
#endif

mycdev.c

#include 
#include 
#include 
#include 
#include 
#include "head.h"

unsigned int major;
char kbuf[128]={0};
gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
unsigned int *vir_rcc;

//封装驱动的操作方法
int mycdev_open(struct inode *inode,struct file *file)
{
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
int mycdev_close(struct inode *inode, struct file *file)
{
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
ssize_t mycdev_read(struct file *file, char __user *ubuf, size_t size, loff_t *lof)
{
    int ret;
    if(size < sizeof(kbuf))
    {
        size = sizeof(kbuf);
    }
    ret = copy_to_user(ubuf,kbuf,size);
    if(ret)
    {
        printk("copy_to_user faild %d\n",__LINE__);
        return ret;
    }
    printk("%s:%s:%d",__FILE__,__func__,__LINE__);
    return 0;
}
ssize_t mycdev_write(struct file *file, const char __user *ubuf, size_t size, loff_t *lof)
{
    int ret;
    if(size < sizeof(kbuf))
    {
        size = sizeof(kbuf);
    }
    ret = copy_from_user(kbuf,ubuf,size);
    if(ret)
    {
        printk("copy_from_user faild %d\n",__LINE__);
        return ret;
    }
    printk("%s:%s:%d",__FILE__,__func__,__LINE__);
    if(kbuf[0] == '1')//控制led1
    {
        if(kbuf[1] == '1')//点亮led1---->PE10
        {
            (vir_led1->ODR) |= (1 << 10);
        }
        else if(kbuf[1] == '0')//关闭led1
        {
            (vir_led1->ODR) &= (~(1 << 10));
        }
    }
    else if(kbuf[0] == '2')
    {
        if(kbuf[1] == '1')//点亮led2---->PF10
        {
            (vir_led2->ODR) |= (1 << 10);
        }
        else if(kbuf[1] == '0')//关闭led2
        {
            (vir_led2->ODR) &= (~(1 << 10));
        }
    }
    else if(kbuf[0] == '3')
    {
        if(kbuf[1] == '1')//点亮led3---->PE8
        {
            (vir_led3->ODR) |= (1 << 8);
        }
        else if(kbuf[1] == '0')//关闭led3
        {
            (vir_led3->ODR) &= (~(1 << 8));
        }
    }
    return 0;
}
struct file_operations fops={
    .open=mycdev_open,
    .read=mycdev_read,
    .write=mycdev_write,
    .release=mycdev_close,
};
int all_led_init(void)
{
    //1.字符设备驱动的注册
    major = register_chrdev(0,"mycdev",&fops);
    if(major < 0)
    {
        printk("字符设备驱动注册失败%d\n",__LINE__);
        return major;
    }
    printk("字符设备驱动注册成功 major=%d\n",major);
    //2.进行LED相关寄存器的映射
     //led1----->PE10
    //led2----->PF10
    //led3----->PE8
    vir_led1 = ioremap(PHY_LED_MODER_E,sizeof(gpio_t));
    vir_led2 = ioremap(PHY_LED_MODER_F,sizeof(gpio_t));
    vir_led3 = ioremap(PHY_LED_MODER_E,sizeof(gpio_t));
    if(vir_led1 == NULL || vir_led2 == NULL || vir_led3 == NULL)
    {
        printk("led寄存器映射失败！%d\n",__LINE__);
        return -ENOMEM;
    }
     printk("MODER寄存器映射成功！%d\n",__LINE__);
    vir_rcc = ioremap(PHY_LED_RCC,4);
    if(vir_rcc == NULL)
    {
        printk("rcc寄存器映射失败！%d\n",__LINE__);
        return -ENOMEM;
    }
     printk("rcc寄存器映射成功！%d\n",__LINE__);
    //3.寄存器的初始化
    //RCC寄存器初始化
    (*vir_rcc) |= (3 << 4);
    //GPIO寄存器初始化
    (vir_led1->MODER) &= (~(3 << 20));
    (vir_led1->MODER) |=(1 << 20);  

    (vir_led2->MODER) &= (~(3 << 20));
    (vir_led2->MODER) |=(1 << 20);

    (vir_led3->MODER) &= (~(3 << 16));
    (vir_led3->MODER) |=(1 << 16);

    (vir_led1->ODR) &= (~(1 << 10));
    (vir_led2->ODR) &= (~(1 << 10));
    (vir_led3->ODR) &= (~(1 << 8));

    printk("寄存器初始化成功！%d\n",__LINE__);
    return 0;
}
static int __init mycdev_init(void)
{
    if(all_led_init())
    {
        printk("led灯初始化失败！\n");
    }
    printk("led灯初始化成功！\n");
    return 0;
}
static void __exit mycdev_exit(void)
{
    //取消内存映射
    iounmap(vir_led1);
    iounmap(vir_led2);
    iounmap(vir_led3);
    iounmap(vir_rcc);
   
    //字符设备驱动的注销
    unregister_chrdev(major,"mycdev");

}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

demo.c

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "head.h"
int main(int argc, char const *argv[])
{
    char buf[128] = {0};
    int fd = open("/dev/mycdev", O_RDWR);
    if(fd < 0)
    {
        printf("设备文件打开失败\n");
        exit(-1);
    }
    while(1)
    {
        //led1----->PE10
        //led2----->PF10
        //led3----->PE8
        printf("请输入要进行的操作：例如（点亮led1输入11，关闭为10）>",buf);
        fgets(buf,sizeof(buf),stdin);
        buf[strlen(buf)-1] = '\0';
        write(fd,buf,sizeof(buf));
    }
  
   
    close(fd);
    return 0;
}